Ore-classifier.



No 849,379. PATENTED APR. 9, 1907.

- J. VAN N. DORR.

ORE GLASSIPIER.

APPLICATION FILED MAY 18. 1906.

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? a) mjwmgb No 849,379. PATENTED APR. 9, 1907.

J. VAN N. DORR. ORE GLASSIFIER.

APPLICATION FILED MAY 18.1906. I

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VII/IIIIIJIIMI/Il/ T stance, the hydraulic cones UNrrnn s'rn'rne JOHNVAN N OSTRAND DORR, OF LEAD, SOUTH DAKOTA.

ORE-CLASSIFIER.

Specification of Letters Patent.

K Patented April 9, 1907.

Application filed May 18 1906. Serial No. 317,583

To all whom it may concern:

Be it known that I, JonN VAN NOSTRAND -DORR, a citizen of the UnitedStates, residing in Lead, in the county of Lawrence and State of SouthDakota, have invented certain new and useful I'm rovements inOre-Classifiers, of which the fo lowing is a specification.

My present invention relates to certain improvements in apparatus forseparating and classifying materials which have different settling ratesin liquid, whether such difference is caused by a variation in thespecific gravity of the particles, as in the concentration of ores, orin the size of the particles when homogeneous, as in the separation ofsands and shmes.

The primary object of my invention is to provide an apparatus which,while simple in construction and easily operated, will thoroughlyseparate the sands or rapidly-settling particles 1n wet crushed pulpfrom the slimes or slowly-settling particles therein and will separatelydeliver the slimes and the clean leachable sands.

My improved apparatus is especially designed for classifying the sandsand slimes in wet crushed pulp for cyaniding, and for convenience I willassume in the followin description that the pulp is being treated forthat purpose.

Ore pulp, as is well understood, contains sands with which metallicvalues are mixed and which is readily leachable and also slimes whichcontain values which cannot be economically leached and which if mixedwith the sands revents or impedes the leach.- ing thereof. uch slimesmay be treated to recover their values; but it is very desirable thatthe process for recovering the values from slimes shall be sc arate anddistinct from the treatment of t e sands to recover the valuestherefrom.

Various forms of apparatus have been devised for classifying sands andslimes; but they have not proved satisfactory in all particulars orunder all conditions. For inheretofore most generally used for theurpose were open to the objection that w ere the pulp contained muchearthy material, producing a large amount of slimes, it was necessary toemploy a strong upward current of liquid in the cones, resulting in thecarrying over with the slimes of a great Cportion of the fine sandswhich would be rea ily leaehable if allowed to remain with the coarsersands, or it was necessary to use several cones in series, making alarge amount of fall or requiring increased rnill height.

According to my invention the wet pulp from a suitable crusher orpulveriper is continuously conveyed to a settling-trough, where thesands settle to the bottom by gravity, while the slimes remain insuspension in the liquid. The slimes flow over into a launder, whichconveys them away to a suitable receptacle removed from the classifier,while the sands are moved upwardly along the inclined bottom of thetrough and delivered to another launder, which conveys them to theleachers or other suitable receptacles. For the pur ose of moving thesands out of the trough em loy rakes or scrapers, whi'ch are reciprocateback and forth above the bottom of the trough in such manner as to movethe sands toward the u per end of the trough on the outstroke, ut whichare elevated above the lane of the sand on their instroke. This re 'noperation is effective not only in moving t 1e sand as fast as it fallstoward the sand-receiving launder, but it also serves to loosen oragitate the sand b first forming it into small piles and then a lowingit to settle, while at the same time progressively moving it upward andoutward along the inclined bottom of the trough. The rakes, whileeffectively removing the sands ,do not so agitate theliquid in the u perstratum of the bath as to interfere with the settling of the sands. Theoperation results in keeplng the slimes in suspension and allowing thesands to settle out, and as the sands are spread out in a thin layer theliquid has a better chance to act upon them.

While the greater portion of the slimes are separated from. the sands inthis way, there are still some present in the settled sands which mustbe removed. To accomplish this, I provide means for washing the settledsands after they emerge from the settling-.

bath and just before their delivery to the launder which conveys themaway. For this purpose perforated pipes are located near thesand-delivery end of the trough, through which clear liquid is forcedupwardly through the sand as it passes over them, resulting in theelimination of the remaining slimes, which are carried back with theincoming li uid to the settling-bath, very little of such 0 car liquidbeing allowed to pass. out with the sands.

. I preferably divide the settling-trough into roe rofz c two parts,using two, sets of rakes operating alternately in opposite directions,whereby the weight of the moving parts is counterbalanced, and theoverflow of the liquid into the slime-receiving trough is made moreuniform and even.

In the accompanying drawings have illustrated the way new best known tome the. sands settle rake.

7 feed-launder. Fig. 5 is a plan view classifier. Fig. 6 shows atransverse section 2 is a longitudinal classifier,

up into piles during the outstroke of the rake. Fig. 3 is on the line'66 of Fig. 1. a I The wet pulp is conveyed by a feed-launder A to asettlingtrough B, which is inclined as shown, the -liquid-level in thetrough being i indicated by the dotted line as.

Suitable supports-B are employed to hold the trough at the desiredinclination. The feed-launder V is preferably of the form illustrated inFig. 4

and extends entirely across the trough, being formed withslots a,through which the wet pulp passes on to a distributing-plate a.Preferably the launder is located about midwaybetween the upper andlower ends of the A launder C for carrying away the and a launder D forcarrying ofi the are located, respectively, at the lower trough. slimessands,

'- and upper ends of the trough. Preferably'the n, which troughis'divided into two parts by a partition is high enough merely toprevent thesands from spreading from one part or division of the troughto the other. In each division of the trough is located a rake orscraper F;comprising longitudinal bars f and a series of transverseplates f, attached to the'ba'rsin any suitable way.- The rake-b ars -5oare supported b hangers G and H, which atitheir upper ends are attachedto crossbars-g, provided with rollers g" at opposite ends,each rollerbeing adapted to travel in a track i,-applied to a plate J, secured to aframe I, arranged-at a slight elevation abovethe top of the trough. Overthe tracks tare arranged gravityswitches 'y', which-are pivoted at j'andwhich are so operated, as

be readily understood fro'm an inspection -'of 'Fig. 1, that when therollers move upwardly, .or'to the'right as viewed in Fig; 1, they willtravel along the jin'clined track 5 After.

' 'reachingthe end of the tracks therol lers p,

b e-regulated. As ward through the sands inthe manner inch--1 0 willlift the switches and then-allow them to drop, and on "thereturamovement of the:

driving-shaft M.

inclined board C,

toward the overflow.

lower or inner end of the seasre rakes the rollers will travel on top ofthe switches until they reach the rear or lower ends thereof, when theywill pass from the switches and again rest on the tracks 6. In this wayas the rakes are moved back and forth they are made to rise and fall atthe proper times, being lowered to a position close to thebottom of thetrough on the outward or upward stroke and being elevated some distanceabove the inclined bottom on the instroke, as illustrated in Fig. 3, butare not entirely withdrawn from the bath.

It will be observed that by the construction shown there is no chancefor wear on the bearings of the rakes. The supports and parts which movein contact with each other are entirely above the liquid-level. If theywere below the liquid-level, they would be exposed to the action of gritand sand, which would soon wear them out.

The rakes in the two compartments or divisions of the trough are similarin all respects, and to each one is joined a connectingrod K, theouterend of each of which is attached to a crank L on a shaft L, gearedto a it will be observed that the cranks radiate in diametricallyopposite directions, so that as the rake in one division of thetrough-moves upward and outward the rake in the other division of thetrough moves inward and downward. This arrangement serves tocounterbalance the weight of the moving parts, and it also serves tomake the overflow into the launder C more steady and uniform.

' Near the launder C, 1 preferably locate an which serves todirect theslimes into the launder, and I also preferably employ a bafile-board Gwhich may be adjusted vertically to regulate the flow of liquid Theposition of the lower edge of the baflie-board determines thecross-section of the stream of slimes passing under it, and thereforeits velocity and carrying power for fine material. Any suitable meansfor adjusting the board 0 may be employed. The devices shown need not bedescribed as the construction and operation may be cleaned are obvious.The trough at the out'when necessary through the pipe C trough.

For the purpose of cleaning the settled sands after their emergencefromthe liquid and just before their These pipes are preferably located inrecesses in the bottom of the settling-trough, as indicated in Fig. 1,and they are provided with -.numerous perforationa'so as to deliverclear liquid, such as clear cyanid solution under pressure, to thesaiids them. The pipes are rovided' with valves which the flow '0th'e'clear liquid may the liquid is forced updelivery to the launder D,I provide a series of perforated pipes.P.

asthe latter pass over cated in Figs. 2 and 3 the latter will beelevated slightly and agitated, while the contained slimes are separatedand flow back into the bath in the manner indicated in Fig. 3. The sameeffect could not be produced by spraying liquid onto the top of thesands after emergence from the bath because such action would not soefficiently act on all the particles of sand and would tend to wash thesands back into the trough.

It will be observed that the settled sand is in motion only half thetime, but is exposed to the action of the upward flow of clear liquidfrom the pipes P both while in motion and also while at rest, thusgiving the liquid ample opportunity to keep the settled sand loose'andopen and to allow the escape of the slimes. This action of the upwardcurrent through the settled sand is quite different from the action ofthe upward current in the hydraulic cones and much more eflicient, asthe amount of clear liquid required is much less, and there is no chanceof currents moving in both directions, which would carry down slimeswith the sands. The inward movement of the rakes causes an agitation ofthe particles in suspension in the lower stratum of the bath, and thustends to free the settling particles of sand from the adhering slime andkeeps the latter in suspen- S1OI1.

Actual experience has demonstrated that perfectly clean leachable sandsare obtained, while the slimes are entirel free from sands. Practicallyall of the liqui from the bath or from the cleaning-pipes can beprevented from assin into the sandereceiving launder, and t e sanddled'by mechanical conveyers, if desired.

My lmproved classifier ossesses many advantages over others. it iscompact, requiring but little space and no elevators. It necessltateslittle attendance, no matter how much the ore may vary in its nature,and

both clean sand and clean slimes are made in one operation. The sand isdelivered practically free from water and most of the clear liquid forcleaning the settled sand is saved, as before stated.

Although my apparatus was especially designed to give the greatestamount of clean leachable sand from wet crushed pulp for cyaniding, itmay alsobe used to advantage to replace the spitzkasten for removing thecoarser sand from the product of a stampmill for delivery toregrinding-mills, where an excess of water is objectionable. It may alsobe employed to deliver clean leachable sand in condition to be drainedand conveyed moist to' leaching-vats, thus providing all the aerationneeded and doing away with the expensive double treatment, and it mayalso be used for se arating fine sands from slimesin can be drained soas to be hanferred to the ra idly-settling particles as sands and totlie slowly-settling particles as slimes; but itwill be understood thatthe apparatus may be emplo ed to classify materials not ordinarily thusesignated, and I wish it understood that both in the specification andin the claimed do not wish to confine my invention to apparatus forseparating sands and slimes.

I claim as my invention 1. An apparatus for classifying crushed ores,comprising a stationary settling-trough to which the ul is delivered andin which the sand sctt es y gravity, means for conveying the settledsands to one end of the trough, means for forcing a clear li id upthrough the settledsands at the sand-delivery end of the trough toseparate the slimes therefrom, and means-for conveying slimes away fromthe bath.

2. An apparatus for classifying crushed ores, comprising an inclinedstationary settling-trou h to which the pulp is delivered,

and in WllOh the sand settles by gravity while the slimes remain insuspension, means for conveying the settled sands upwardly along thelnclined bottom of the trou h, and means for forcing a clear liquid up trough the settled sands to separate slimes therefrom at thesand-delivery end of the trough and to cause. said slimes to pass backto t e settling-bath.

3. An apparatus for classifying crushed ores, comprising an inclinedstationary settling-trough in which the sands settle and the slimesremain in suspension, a reciprocatin rake for moving. the settled sandsupward y and outwardly in the trough, and means at the sand-delivery endof the trough for forcing clear liquid up through the sands after theiremergence from the settling-bath, andhwhile being conveyed away from thebat 4. An apparatus for classifying crushed ores, comprising an inclinedstationary setthug-trough in which the sands settle to the bottom whilethe slimes remain in suspension, a reciprocating rake engaging thesettled sand on its outstroke. and moving it toward the upper end of thetrough, means for lifting the rake out of engagement with the sand onthe instroke, and means for washing the sand to remove the slimetherefrom arranged at the sand-delivery end of the trough and actingupwardly through the settled sand.

5. An apparatus for classifying ore-pulp comprising a settling-trough,two rakes arranged side by side in the trough, a partition in the lowerpart of the trough, the upper edge of which is below the liquid-level,for dividing the sands under one rake from the sands under the otherrake, mechanism for reciprocating the rakes alternately in oppositedirections whereby the weight of the moving parts is counterbalanced andthe overflow from the trough is' equalized, a launder for receivingslime at the lower end of the'trough, a launder for receiving sand atthe opposite end thereof and a feed-launder for the pulp arranged.intermediate'the ends thereof.

6. An apparatus for separating and classifying materials of differentsettling rates, comprising a stationary settling-trough, a launder forreceiving materials remaining in suspension in the trough, a launder forreceiving the settled material, means for conveying the settled materialtoward its receiving-launder, and means for forcing a'clear' liquid upthrough the settled material asit emerges from the settling-bath andbefore its delivery to its receiving-trough.

7. An apparatus for separating and classifying materials of differentsettling rates, comprising a stationary trough containingasettling-bath, a launder at one end of the trough for receiving materialremaining in suspension in the liquid, a launder at theopposite end ofthe trough for receiving the settled material, a reciprocating rakemoving outward while engaging the settled material, means for elevatingthe rake above the settled material on the instroke without Withdrawingit entirely from the bath mechanism for operating the rake and means forforcing a clear liquid up through the settled material as it emergesfrom the settling-bath and before its delivery to its receivinglaunder.

8. An apparatus for classifying crushed ore comprising a stationarysettling-trough to which the pulp is delivered and in which the sandsettles by gravity while the slimes remain in suspension, means forconveying the sands from the trough without disturbing the settlingaction in the upper portion of the bath, and means for forcing clearliquid up through the settled sands after their emergence from the bath.o

9. An apparatus for separating and classifying material of differentsettling rates, comprising a stationary settling-trough, a launder forreceiving material remain ing in suspension in the trough, a launder forreceiving the settled material, means below the liquid-level of the bathfor conveying the settled material toward its receiving-launder,

means above the liquid-level for supporting the conveyer, and means foroperating the conveyer.

In testimony whereof 1 have hereunto sub scribed my name.

JOHN VAN NOSTRAND DORE.

Witnesses:

G110. B. THOMPSON, G. L. GIL'LIs.

